The unnamed plant in the southern province of North Brabant is being checked as part of an investigation into an estimated 100 firms by the prosecutor's office and the government's food and consumer watchdog, the NVWA.

Norway and Austria are the latest two European countries to find horsemeat being sold as beef, discovering it in ready-to-eat meals.

Previously, the mislabelled meat was discovered in the UK, the Republic of Ireland, France, Switzerland, Sweden and Germany. Suspicious products have also been withdrawn in the Netherlands as tests are conducted there.

French supplier Spanghero has apologised to UK consumers over the horsemeat, but denied selling it deliberately.

Month of tests

The widening scandal has highlighted the complexity of the food industry's supply chains across Europe.

Meat scandal

In mid-January, Irish food inspectors announced they had found horsemeat in some burgers stocked by UK supermarket chains

Subsequently, up to 100% horsemeat found in several ranges of prepared frozen food in Britain, France, Switzerland, Germany, Sweden, Austria and Norway

Concerns that a drug used to treat horses, and which may be harmful to humans, could be in food chain

Meat traced from France through Cyprus and the Netherlands to Romanian abattoirs

Investigation suggests adulteration was not accidental but the work of a criminal conspiracy

Under the EU plan announced on Friday, 2,250 processed beef samples will be tested across the EU, ranging from 10 to 150 per member state. The samples will come from foods on sale in retail outlets and marketed as containing beef.

Separately, tests will be conducted for possible residues in horsemeat of phenylbutazone, also known as "bute".

The testing regime will be one sample per 50 tonnes of horsemeat, and each country will carry out a minimum of five tests. Phenylbutazone is a veterinary medicine whose use in livestock, including horses, is illegal.

On Thursday the FSA said eight horses killed in the UK had tested positive for bute, and meat from six of them may have entered the food chain in France.

European press reaction

An editorial in the French left-wing daily Liberation says there is "collective cowardice" in the horsemeat scandal.

"Everybody is passing on the hot lasagne to their neighbour. In the realm of unhealthy eating, everybody is irresponsible."

Germany's Sueddeutsche Zeitung describes the fraud as "criminal, huge and tasteless". But it says the behaviour of German consumers is "in fact hugely tasteless too".

In the German Frankfurter Allgemeine Zeitung, a commentary says "a whole nation shudders as if waste oils had been mixed into its muesli".

Romania's English-language daily Nine O'Clock attacks reporting of the scandal in the UK press, saying "the Brits are far from getting rid of stereotypes... the horsemeat scandal only worsens the fear and aversion towards Romanians".

"The French government put us to death," he added. Veterinary inspectors are visiting Spanghero's premises in southern France.

In the UK three people were arrested for suspected fraud in meat sales on Thursday.

And on Friday catering giant Compass Group and Whitbread, one of Britain's largest hotel chains, said it had found horse DNA in products sold as beef.

Some of the affected burgers and lasagne had been supplied to pubs and schools in the UK and Ireland.

Meanwhile, the UK's Food Standards Agency (FSA) said that after 2,501 fresh tests no new products had been identified as containing more than 1% horsemeat. It said the 29 positive results were on seven previously withdrawn products.

'Conspiracy'

In France, ministers said they believed the sale of horsemeat labelled as beef went on for six months and involved about 750 tonnes of meat.

Spanghero imported meat from Romania and sold it on to another company, Comigel, which made frozen ready meals at its factory in Luxembourg for further distribution.

Millions of processed meat products have been withdrawn from supermarket shelves across the EU.

The UK has asked the European investigative agency Europol to co-ordinate a continent-wide investigation into an alleged international conspiracy to pass horsemeat off as beef.

French food producer makes order

Comigel HQ in Metz, north-east France, asks its subsidiary, Tavola in Luxembourg, to make food products - including beef lasagne for Findus.

Factory orders meat

The Tavola factory orders the meat from Spanghero in the south of France.

Subcontractor used

Spanghero contacts a subcontractor in Cyprus to source the meat.

Subcontractor enlists trader

The Cypriot subcontractor in turn contacts a trader in the Netherlands.

Trader orders from Romania

The trader in the Netherlands places an order for meat with abattoirs in Romania.

Abattoirs send meat to France

The meat from the abattoirs travels to Spanghero in France. However, Romania rejects claims that it was responsible for wrongly describing the horsemeat from its abattoirs as beef. Horsemeat is always labelled as such, they say. The Romanian authorities claim records show orders had been for horse carcass - easily distinguishable from beef.

Meat used to make products

Spanghero sends the meat to the Comigel subsidiary’s factory in Luxembourg before the finished products are supplied to Findus and retailers across Europe, including the UK. The president of Comigel says the company was unaware the meat was coming from abroad.

Horsemeat found in Ireland and UK

Tests by Irish authorities have found equine DNA in beefburgers made by firms in the Irish Republic and the UK. Traces of horsemeat have also been found in stored meat at another plant in Ireland and one in Northern Ireland. In mainland Britain, police and officials probing alleged horsemeat mislabelling have carried out raids at a slaughterhouse in West Yorkshire and a meat firm near Aberystwyth. Three men were later arrested on suspicion of offences under the Fraud Act..

More on This Story

Analysis and background

The discovery of horsemeat in processed beef products sold by a number of UK supermarket chains has resulted in tests by regulators across Europe and prompted a number of product recalls. How did the scandal unfold and what is being done?

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